


Alexander.

by thelordofstarsanddreams



Category: Shadowhunters (TV), The Mortal Instruments Series - Cassandra Clare
Genre: Alternate Universe - BDSM, Anal Fingering, Anal Sex, BDSM, BDSM Scene, Collars, Consensual Sex, Dating, Dom Magnus, Dom Magnus Bane, Dom/sub, Dom/sub Play, Humiliation, M/M, Minor Humiliation, Praise Kink, Punishment, Relationship(s), Spanking, Sub Alec, Sub Alec Lightwood, Switch Magnus
Language: English
Status: Completed
Published: 2017-04-02
Updated: 2017-04-02
Packaged: 2018-10-14 04:36:40
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 2,906
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/10529085
Author URL: https://archiveofourown.org/users/thelordofstarsanddreams/pseuds/thelordofstarsanddreams
Summary: The discovery of Alec Lightwood being a submissive had been a surprise for most to say the least.Shadowhunters tended to always be dominant. Especially the Lightwoods.Each generation had hosted strong doms who had birthed the next line and so on. Yet it seemed Alexander had missed that quota entirely. Being a gay, sub didn't exactly fit the prime description for the ideal Shadowhunter.Dating Magnus Bane had just tipped him over that scale entirely.





	

**Author's Note:**

> This fic is once again proof that I have a complete inability to write anything under 1000 words. Anyway, this is a prompt and fic promised to a friend a long time ago (and I mean a long time ago) and I've finally got around to finishing it. It's a funny little throwaway idea based on the idea of Magnus wearing Alec's collar to make a point and it went from there. It's been written at different stages and times of the night and I haven't written anything in a while so do be kind and enjoy.

The discovery of Alec Lightwood being a submissive had been a surprise for most to say the least. 

Shadowhunters tended to always be dominant. Especially the Lightwoods. 

Each generation had hosted strong doms who had birthed the next line and so on. Yet it seemed Alexander had missed that quota entirely. Being a gay, sub didn't exactly fit the prime description for the ideal Shadowhunter. 

Dating Magnus Bane had just tipped him over that scale entirely. 

The warlock was so confident in everything he was. A bisexual, switch, the minute he had met Alexander, he'd sensed the boy's potential to be a submissive despite how desperate he clung to the title of dom. 

There had been a lot of denial, and after the whole fuss with Lydia, it was only then that Magnus was finally able to guide Alec very gently into his acceptance of not only being gay, but being a sub as well.

Maryse had really found reason to hate the warlock on all fronts thanks to that.

Now, months down the line, Alexander had flourished into the perfect sub. The man was eager, obedient, he listened to Magnus and very rarely went against him and when he did, his punishment had been accepted with understanding and acceptance. Of course, there had been a few moments of trial and error. That was always the case with someone so new to everything, but eventually, they had settled into a routine, learning everything there was to know about one another.

Discipline was something the warlock almost never had to issue against the Shadowhunter. The man was trained in the ways of self-control and how to follow rules, so when Magnus told him to do something, it was unlikely he would fail in respecting the command. Yet on occasion, even Alexander slipped up.

The incident in question, Alec had been given such a simple request. After the mission, he was to message Magnus and let him know he was home safe. It meant the warlock didn't worry when the Shadowhunters went off playing the heroes.

Only hours after they were due to return, there was still no message.

Nothing.

Silence. 

Izzy was the one who contacted him in the end. Casually wondering if he could bring some elixirs to the Institute the next time he was around as they had run out. Almost immediately he had questioned about his boyfriend. Was Alexander okay? Was he safe? What had happened?

Apparently it had been a routine mission, only a few scrapes and bumps, everyone was home safe. But Alexander had simply forgotten to let the warlock know he wasn't dead. 

Naturally, Magnus wasn't happy. 

And an hour after his conversation with Izzy, he finally received a message from Alec. He hadn't been his usual warm self and while he was glad the man was safe from the mission, he had no intentions of letting Alexander's moment of forgetfulness go unnoticed and he made that clear.

Only to have his boyfriend offer him a snark message in response.

Alec was pushing his luck with his dom. 

And Magnus was not happy. 

\-------------------------------------------------------------------------------------------------

When it came to punishing Alec, it required a certain degree of thought. Pain and physical punishments, while getting a point across, didn't hold the same effect as they did for most. Shadowhunters were much too tolerant. Yet everyone had something, and Magnus had found that when it came to his Alexander, discipline was a much more elegant affair. 

Desperation, teasing, over stimulation, humiliation. 

It had taken time, but Magnus had found all those things got through to Alec in a way a spanking never could. Yet there was something delightful about his favorite Shadowhunter getting off on some degree of humiliation.

And that had been his line of thinking as he'd arrived at the Institute the next morning, having giving them all enough time to recover from the nights previous mission.

Alec had sent him a slightly sheepish message a few hours previous, apologizing, though Magnus had ignore it, simply telling his boyfriend that he'd be coming to the Institute with some tonics and he expected to see him when he was there. 

Those within the glamored church were used to Magnus, striding through the halls in his elaborate clothes either to help or visit as was needed. In one hand, he clasped a case of tonics, and the only thing different today was tied to his accessories. Or rather, the collar which sat snug against his neck.

It was black leather, expensive ever to look at, with a silver buckle that had detail etched into the surface if you looked close enough. Magnus had had it made special.

For Alec.

The Shadowhunter was not one for bringing their private lives into public, but this was subtle. It wasn't out of the question for Magnus to wear such a thing, and the only person who would know exactly what it was and who it belonged to, was his boyfriend. 

Intentionally, the warlock had wore a shirt that he was able to open, the collar flattened so the black leather stood more prominent tucked against his neck.

The Lightwoods were gathered around a table in the main body of the building, Alec at the head of the table while Izzy and Clary lingering over maps and diagrams. With Aldertree gone, Jace had moved back into the Institute and was currently propped in a chair mulling over a book, looking as serious as always. 

“Good morning all,” Magnus' voice was light and breezing as he arrived at the table, setting the case of tonics and elixirs onto it. “A restock as promised,” He looked pointedly at Izzy, offering her a gentle smile, before letting his sweeping gaze settle on Alec. The eldest Lightwood was staring at him, a pink tinge already coloring his cheeks and tops of his ears, unable to tear his eyes from the collar at his neck.

“Alexander,” He greeted, trying to bite back on the smirk that was playing on his lips, especially as Alec looked like he might throw something at him or crawl under the table to hide. 

And Alec wasn't the only one looking.

Jace had lifted his head as Magnus had approached and had also zoned in on the collar. He had seen it before, but that last time, it hadn’t been Magnus who was wearing it. Yet it was unmistakable. The same as it had been when it had been tightened around Alec's neck as the man had made coffee in the kitchen early one morning after staying at the warlock's when Jace had still been staying with him. The recognition was there, quickly followed by an amused smirk and near laughed that he dipped his head to hide.

“Magnus, could I speak to you for a moment. In private?” Alec's voice was polite yet sharp, a certain hidden bubble of urgency masked beneath that normally steady tone and the man was attempting to avoid looking at the warlock entirely now.

“I'm sure anything you need to say, Alexander, you can say here.”

Of course he couldn't. He could only imagine all the things Alec wanted to spit at him, none of which could be shared among their friends and his family. 

With a near dismissive smirk, Magnus brought his fingers up to tease along the collar at his neck, humming as he looked down at maps and diagrams. “So Shadowhunters, what are we researching today?”

Honestly, the warlock wasn't listening as the group launched into the talk of the mission, instead meeting the glares his boyfriend was passionately shooting at him in regular intervals.

“That collar is so cute, where did you get it?”

It was Izzy who drew attention to the item this time, the Lightwood woman always could appreciate accessories, and she leaned in eagerly to inspect it, not knowing that it normally graced the neck of her brother as opposed to Magnus.

“It's Italian, custom made by a designer in Venice who specializes in such art. It was a gift,” And it was, just not for him. Magnus tended to like his subs to wear an array of collars, of all colors and effects, but Alec was a bit stubborn, so he'd went for something much more Lightwood for the man with as much care and effect having gone into procuring it. 

“It's adorable. Clary would suit one. Does it come in colors? Purple would be nice.”

“It does actually, he also does fabulous detailing, even inscriptions, I was going to get this one-”

“Magnus. Office. Now. I need a word.”

Alec's voice was as sharp as a knife, slicing through the conversation he'd been enjoying with Izzy, and with an apologetic pat to the woman's arm, he stepped away from the table, following Alec who was already making a beeline for the office, normally occupied by visiting officials from Idris, quite often a Lightwood. 

Luckily, it was vacant. 

“What the hell, Magnus?” The door had barely slid shut when Alec's voice broke the silence and with an easy expression the warlock turned to face his boyfriend.

“Problem, Alexander?”

“You know exactly what the problem is, why are you wearing that?” The man made an exaggerated gesture towards Magnus' neck, earning a small shrug from the man in return.

“I don't know what you mean, I'm merely accessorizing,” The warlock once again traced the collar at his neck, watching as that blush crept back onto Alec's face, the man looking completely flustered.

“It's mine.”

“Possessive aren't we?”

“You know we only have that for me to wear in private.”

“Well, given your ability to disregard my rules and request that you let me know you aren't dead after a mission, perhaps I've decided to ignore the fact that this collar is only for your use.”

Silence.

That familiar scowl on Alec's features told him that the man knew he was in the wrong, that he'd been caught yet he still wanted to fight it. So typical of the Shadowhunter. 

“I got caught up. Distracted after the mission. I didn't have time.”

“Izzy had time. It would have taken moments to message me Alexander. I have one rule when it comes to you and your missions and that is to check in with me when they are over.”

“I know, but-”

“No more excuses, Alexander,” 

Magnus' voice left no room for argument, the sharp, dismissive tone that he only used when Alec did something that earned his disapproval, which wasn't often. There was a pause, but no further argument from the man.

“Sorry, sir.”

That was more like it. 

Stepping forward, Magnus slid his hands up to his own neck, unfastening the collar and removing it so he could reach up and slide it around Alec's neck, securing it. Back where it belonged. And it was beautiful on him. 

“It's okay. Tell me, do you think you deserve a punishment, my dear?”

There was a pause, before Alec gave a slow nod, his eyes big and wide, like a puppy that had already been kicked. It was hard to ever think of disciplining such a beautiful creature. Magnus trailed his hands down from Alec's neck, along his chest to rest at his hips. 

“Shouldn't we wait? Until later? We can go to your apartment.”

“I think now is as good a time as any.”

The conflict in Alec's eyes was something he knew well. When the man wanted something but was tied by logic and fear. The others were just outside, had Magnus even locked the door? This office wasn't assigned. Anyone could walk in. And so close to the main rooms, someone, anyone could hear them. The Shadowhunter gave a slight squirm, cheeks flushed, a slight huff of breath echoing from him. Magnus already knew what side of the man was winning.

“Yes, sir.”

“Good boy.”

\-------------------------------------------------------------------------------------------------

The harsh slap resonated throughout the office, breaking the silence, followed by a slight grunt and murmur from Alec. 

The Shadowhunter was bent over the mahogany desk, gripping the edges, pants around his ankles as Magnus spanked him, one hard slap after the other, the skin of his ass already reddening. 

“Count louder, Alexander. I want them to be able to hear next door.”

There was a teasing lull to the voice of the Warlock, yet Alec froze slightly against the desk, the number dying on his lip as he cast a glance over his shoulder. “You didn't cast a silencing spell?” 

The smirk on Magnus' lips answered his question. “I'd rather they heard how pretty you sound when you're getting spanked. Now, do we need to start again or can you remember how to count?”

A hesitation.

“Fifteen.”

“What was that?”

“Fifteen, sir.”

“Good boy.”

The harsh slaps continued, Alec counting each of them out, trying to ignore the niggling worry that someone would over hear or barge in on them. 

Twenty and Magnus stopped, giving the Shadowhunter a moment to breath, his forehead pressed to the cool wood of the desk, recollecting himself. It would be difficult, having to face everyone again when he'd just been spanked. Not to mention he was painfully hard, squirming against the desk for just a little bit of friction, in hopes that he could grant himself a little relief before he had to pull his pants back up and face his friends.

Yet the soft dismissal of his dom never came, and Alec was about to speak out of term and question it when he felt cold, slick fingers press against him, causing him to gasp slightly, gritting his teeth. That fucking bastard. 

“Should I stop, Alexander?” It was as if Magnus read his mind, and Alec could hear the smugness to his tone of voice. Of course the warlock would want to fuck him over the desk in the main office of the Institute. Why was he surprised? 

“No, Sir. Don't stop. Please.”

“That's what I thought.”

Two fingers slid inside of him, well lubed, skilled. Thank the angel for Magnus and his magic. He was worked open, slowly but surely, a third digit slipping inside of him, baiting a low groan from Alec, arching back into the touch. This was obscene, yet the Shadowhunter found that the fear of getting caught, of being heard, wasn't enough to stop this, to stop him from wanting this. And when Magnus slid into him, Alec didn't care if the whole of the Institute heard him as he moaned, savoring the feel of his warlock. 

Magnus' nails scraped down over his sides, gripping his hips, hard enough that Alec hoped it left bruises. The man wasted no time, setting into a hard, deep pace, living for the gasps and moans that tumbled ceaselessly from Alec's parted lips, his eyes shut and face flushed. Every day Magnus was certain that his boyfriend was the most beautiful creature he'd ever seen. 

“Alexander...”

The sound of his name, tight with pleasure on Magnus' lips had a near whimper rattled from Alec as he pushed himself upright slightly, body flush against the other man's so he could turn his head, Magnus already moving to catch his lips in a hungry kiss as his hand moved to curl around Alec's cock, jerking him quickly in time with each thrust. 

“Come for me, Alexander,” It was an instruction. A demand. And as Magnus' rough thumb teased over the tip of his length, continuing to stroke him roughly in time with each deep thrust, it was a command he was happy to fulfill. He came, hard. Almost certain his knees might buckle beneath him as a strangled cry ripped from him, filling the room. Moments later, Magnus followed suit, filling him and groaning into Alec's shoulder as he bit down on his pale skin. 

Neither of them spoke for a few long moments, neither of them could. Their ragged breaths the only sounds exchanged, until Magnus finally broke the silence. “So, I assume you've learned your lesson, Alexander? A text message after a mission is appreciated.”

A low, honest chuckle grumbled from Alec as he mumbled, “Fuck you, Bane.”

“I'm all worn out from fucking you, but maybe later.”

Another laugh.

The room stank of sex, Alec noted as they two of them cleaned up and redressed, though Magnus thankfully used his magic to clean the desk and the two of them, muttering a few words to take down the wards he had placed on the room, catching the glare Alec gave him. “What? I never said I didn't cast the silencing spells, you merely assumed.” Alec's face was flushed as he reached up to undo the buckle of the collar, only to have Magnus stop him. “Keep it on, darling. Since you were so offended by my wearing it.”

“I can't wear it out there,” Alec cast a tentative look towards the door, his fingers still against the leather around his neck. 

“Why not? It suits you perfectly.”

“Is that an order?”

“I believe it is.”

With a sigh, Alec dropped his hands from his neck, pulling the collar of his shirt up to hide the fine strap slightly, Magnus smiling as he stepped forward, drawing his Shadowhunter into a kiss. “Good boy. Now, come on, there's work to do and I would hate for someone to catch us in here.” 

Alec rolled his eyes, grumbling under his breath as Magus took his hand and led him from the office.

**Author's Note:**

> If you got to this point, thanks for sticking the fic out till the end and feel free to comment and kudos <3


End file.
